According to CSN Bay Area's Matt Maiocco, the 49ers had to promote or cut Hall --- a third-year, practice-squad player -- because they had an open roster spot.

The 49ers have not formally announced whether Michael Crabtree's playing status will be affected by his involvement in a San Francisco Police Department's sexual-assault investigation.

The only other wide receivers on the 49ers' roster for Sunday's NFC Championship game in Atlanta are Randy Moss, Ted Ginn Jr. and A.J. Jenkins. Mario Manningham and Kyle Williams were lost to knee injuries earlier this season.